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arXiv · 0708.2143

Spin-transfer torques in anti-ferromagnetic metals from first principles

Yuan Xu·Shuai Wang·Ke Xia
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Abstract

In spite of the absence of a macroscopic magnetic moment, an anti-ferromagnet is spin-polarized on an atomic scale. The electric current passing through a conducting anti-ferromagnet is polarized as well, leading to spin-transfer torques when the order parameter is textured, such as in anti-ferromagnetic non-collinear spin valves and domain walls. We report a first principles study on the electronic transport properties of anti-ferromagnetic systems. The current-induced spin torques acting on the magnetic moments are comparable with those in conventional ferromagnetic materials, leading to measurable angular resistances and current-induced magnetization dynamics. In contrast to ferromagnets, spin torques in anti-ferromagnets are very nonlocal. The torques acting far away from the center of an anti-ferromagnetic domain wall should facilitate current-induced domain wall motion.

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Yuan Xu, Shuai Wang, Ke Xia. 2008-06-04. Spin-transfer torques in anti-ferromagnetic metals from first principles. https://doi.org/10.1103/physrevlett.100.226602

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